G418 selection - (Jun/29/2006 )
I am doing G418 selection for HAEC infected cells at 500ug/ml. All the control cells are dead and few healthy individual cells are remaining on the selction plate by Day 7.
Since I have to wait for the cells to increase in number for them to be picked up (and also some dead cells still attached to the plate), do I continue to add G418 to the medium to have the just G418 resistant cells growing. If yes what is the concentration I should use. Once I pick individual colonies can I I stop adding G418.
You should add G418.
I always add G418 when I work with stable cells because I want to be sure I'm working with cells expressing the prot of interest. For any reason, a cell can loose the resistence/gene of interest and if it happens you don't want it to survive...